Hayabusa Immortal

I usually order several OEM filters at once ($9 each) at Sunrise - 800.992.0127. Haven't ordered anything in a few months so I don't know if they still honor the old discounts. You can also get K&N oil filters for about the same price which some people have been using.

Other than that, just check for chain slack, throttle cable slack and make sure all your bolts are tight.

Look here for the service manual which will answer all of your questions and more: